Vitamin C and vitamin B12 are essential water-soluble vitamins. Vitamin C aids in tissue growth and repair, acts as an antioxidant, and supports the immune system. It is found in many fruits and vegetables. A vitamin C deficiency can cause scurvy. Vitamin B12 is important for brain and nervous system function as well as blood cell formation. It supports energy production and cardiovascular health. Good sources are animal products. Deficiency can lead to megaloblastic anemia. Both vitamins have recommended daily intake amounts to support health.